Aquatic plants, bioaccumulation

Food Chain Bioaccumulation. Lead is bioaccumulated by terrestrial and aquatic plants and animals (Eisler 1988). However, lead is not biomagnified in terrestrial or aquatic food chains (Eisler 1988). No additional information is needed. 

System 20. aquatic plants—bentos, plankton, coastal aquatic plants (XII) aquatic animals including bottom sediment invertebrates, fishes, amphibians, mammals, vertebrates, their biological reactions and endemic diseases (VIII) aerosols, atmospheric air (31, 32)—foodstuffs, forages (XV). Human poisoning through consumption of fish and other aquatic foodstuffs with excessive bioaccumulation of pollutants is the most typical example of biogeochemical migration and its consequences. 

Bioaccumulation of Some Forestry Pesticides in Fish and Aquatic Plants... 

Corbet et al. (1983) reported that a rooted plant species (Potemagetonpectimatus) and a surface-dwelling duckweed (Lemna sp.) accumulated concentrations of 1,3,6,8-TCDD of 280 and 105 ng/g (dry weight), respectively, following exposure to water containing 1,000 ng/L (ppt). The maximum concentrations were observed 8 days post-application and represented 6% of the total TCDD applied. These results are similar to those reported by Tsushimoto et al. (1982) in an outdoor pond study, in which a maximum bioaccumulation of 2,3,7,8-TCDD in the pond weeds Elodea nuttali and Ceratophyllon demersum equivalent to a BCF of 130 occurred after 5 days of exposure. In both studies, the tissue concentrations reached equilibrium in approximately 20 days and remained constant until the end of the experiment (approximately 58 and 170 days, respectively). These experimental data indicate that CDDs can accumulation in aquatic plant species through waterborne exposure. 

Highly toxic to fish and aquatic plants. Has die potential to bioaccumulate and is not readily biodegradable. 

Aquatic vascular plants and macroalgae can take up TNT dissolved in water very efficiently as indicated by removal rates determined for several species [11,12] some of which are promoted for use in phyto-treatment of explosives-contaminated water [11]. Less efficient removal of dissolved RDX was reported for wetland and aquatic plants [13,14], Efficient biotransformation and elimination mechanisms in aquatic vascular plants and macroalgae resulted in a lack of bioconcentration of TNT and its solvent-extractable transformation products [11,12], This chapter summarizes and discusses the bioconcentration, bioaccumulation, biotransformation, and toxicoki-netic processes of explosives in aquatic organisms. 

The sources of heavy metals to wetlands, while in some part from natural sources, are dominated by human activity. Natural weathering of rocks introduces some metals into wetlands. However, the majority of elevated heavy metal inputs are from industrial sources. Humans have allowed the surface water to be the prime repository of waste materials including industrial sources. These waste materials include heavy metals that are toxic to aquatic plant and animal life. As a result, there are now concerns with secondary impacts the bioaccumulation and bioconcentration of metals (e.g., Hg) through the food chain that result in toxicity to the nonaquatic species. The atmosphere can also contribute large amounts of heavy metals through emissions from industrial sources which are deposited by both dry aerosol fallout and wet scavenging as precipitation into watersheds. 

Aquatic organisms Acute test fish (2x) and Daphnia, long-term/chronic test fish and Daphnia, algae, aquatic plant for herbicides, sediment organisms, bioaccumulation study Mainly a.i. tests... 

Ecotoxicology data indicates that there is low concern for acute toxicity to fish, aquatic plants, and aquatic invertebrates. The data indicate that the material is not readily biodegradable however, due to the low water solubility, environmental exposures are expected to be low. There is a low potential for bioaccumulation. 

Not readily biodegradable. Log Pow value = 8.51, indicates a high potential to bioaccumulate in aquatic organisms. Direct photolysis t(l/2) 0.6 hrs. Ecotoxicity (LC50 96 hour) 0.23 pg/L [Fish] (EC50 48 hour) 0.038 pg/L [Daphnia] (EC50 96 hour) 0.349 pg/L [Aquatic Plants],... 

S Wang, CM Wai. Supercritical fluid extraction of bioaccumulated mercury from aquatic plants. Environ Sci Technol 30 3111-3114, 1996. 

Food Chain Bioaccumulation. There are a few studies to determine residues of methyl parathion in organisms in the environment. These have consistently shown low methyl parathion residues, indicating that methyl parathion does not bioconcentrate to a significant extent in aquatic organisms, plants, or animals (Crossland and Bennett 1984 Sabharwal and Belsare 1986). The methyl parathion that does get into organisms is rapidly degraded (Sabharwal and Belsare 1986). Some recent analyses of fish in a... 

Food Chain Bioaccumulation. Endosulfan is bioconcentrated by aquatic organisms (Ernst 1977 Novak and Ahmad 1989 NRCC 1975 Roberts 1972 Schimmel et al. 1977) but not by plants or animals (ERA 1982a). The compound is metabolized by terrestrial (Coleman and Dolinger 1982 El Beit et al. 1981c Martens 1977 NRCC 1975) and aquatic organisms (Cotham and Bidleman 1989), and it does not biomagnify to any great extent in terrestrial or aquatic food chains (HSDB 1999). No additional information on the bioaccumulation of endosulfan is needed at this time. 

Food Chain Bioaccumulation. Information is available regarding bioaccumulation potential in aquatic food chains. Studies show that trichloroethylene has a low-to-moderate bioconcentration potential in aquatic organisms (Pearson and McConnell 1975) and some plants (Schroll et al. 1994). Information is needed, however, regarding bioaccumulation potential in terrestrial food chains. 

Mercury (Hg) contamination is widespread in water, in surficial soils and sediments, and in the tissues of plants and animals in ecosystems around the globe. Once deposited to terrestrial and aquatic ecosystems, some inoiganic mercury is transformed into methylmercury (MeHg), a highly toxic compoimd that bioaccumulates efficiently in food webs (Wiener et al. 2003). As a result of the toxicity of MeHg to wildlife and humans, many nations are interested in reducing environmental mercury contamination and associated biotic exposure (UNEP 2002). 

Food Chain Bioaccumulation. Information about americium the levels of americium in aquatic and terrestrial organisms and its bioaccumulation in these organisms is available (Fresquez et al. 1999 DOE 1996 Suchanek et al. 1996). Data are also available on the uptake of americium in plants (Bennett 1979 Cataldo et al. 1980 EPA 1979 Romney et al. 1981 Schreckhise and Cline 1980 Schulz et al. 1976 Zach 1985) and levels in food (Bennett 1979 Cunningham et al. 1989, 1994 Robison et al. 1997a, 1997b). These data indicate that americium does not biomagnify in the food chain (Bennett 1979 Bulman 1978). 

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